Which means you need disable KMS for amd and intel card. Add following to Kernel Parameters.

i915.modeset=0 radeon.modeset=0

newer versions of the Xorg Intel/i915 driver require KMS to work; without it the X server will fallback to framebuffer mode, with poor performance. The underlying issue is that the Intel KMS driver selects the wrong video output; to fix this try the following settings (tested on an 8,3/17" MBP):

radeon.modeset=0 i915.modeset=1 i915.lvds_channel_mode=2

This should give you Intel graphics output. Note that this requires kernel 3.5rc1 or higher; use linux-mainline from Aur if necessary. See this bug for more details.

If you don't have KMS for intel driver, you need install 'xf86-video-fbdev'

# pacman -S xf86-video-intel and xf86-video-fbdev

If Xorg refuses to start with a "no screens found" message you may have to tell Grub2 to turn off the Radeon card and turn on the Intel card during boot. Edit /etc/grub.d/00_header and add the "outb" lines immediately after "set gfxmode=" (Tested on an 8,2 MBP):

Two finger scrolling and left-click works out of the box. Unfortunately the right-click is not functional.

14/09/2012 : right click (2 fingers) and middle click (3 fingers) works out of the box with KDE.

To enable most of the multitouch touchpad features (even right and middle clik) use mtrack, which is avaible in AUR. The configuration is done via the /etc/X11/xorg.conf.d/10-mtrack.conf file. Check if the mtrack module is properly loaded in the /var/log/Xorg.0.log file. Sometimes xorg loads other drivers before, like eg. synpatics, and the mtrack driver is not used at all.

For an MBP 8,3 I needed to use the following config (in /etc/X11/xorg.conf.d/10-mtrack.conf) to stop it picking up other input devices by mistake:

With linux-mainline

As noted elsewhere in this document, some MBP features work best (or only) with the latest kernel; the usual way to install this is using the linux-mainline AUR package. However, as of 3.6.rc3 the config for linux-mainline disables webcam support (due to changed defaults in kernel). This patch to the x86_64 config fixes this issue.

Others that works-out-of-the-box

Sensors

Troubleshooting

Grub2-EFI boot: Intel invalid ROM contents

If you see this error on boot and notice the screen output seemingly frozen, you need to disable KMS.

Append the following to your /etc/grub/defaults LINUX line:

i915.modeset=0 radeon.modeset=0

However, newer versions of the Xorg Intel/i915 driver require KMS to work; without it the X server will fallback to framebuffer mode, with poor performance. The underlying issue is that the Intel KMS driver selects the wrong video output; to fix this try the following settings (tested on an 8,3/17" MBP):

radeon.modeset=0 i915.modeset=1 i915.lvds_channel_mode=2

This should give you Intel graphics output. Note that this requires kernel 3.5rc1 or higher; use linux-mainline from Aur if necessary. See this bug for more details.

You may find you need to enable the Intel device; if using Grub, the following should enable it at boot time: